Last week we told you about some foreign schools that are starting to deliver educational lessons, and teacher feedback, via mobile devices like the iPhone. This story from CNN predicts that within the next couple of years, credit cards will become as obsolete as vinyl records since everyone will be paying their bills via smart-phones.

You can already use your iPhone, Droid or BlackBerry to buy a hotdog at the ballgame, buy your Starbucks latté, or give a friend a few bucks by Bumping phones. But by the end of the year you may not even think twice about reaching for your phone to pay at the register instead of fumbling for your credit card.

"Your plastic card hasn't changed since the age of the vinyl records," said Michael Abbott, CEO of Isis, a new mobile payment network. "This is the chance to bring payments forward from the plastic age and the vinyl records age to the digital age."

While companies have been experimenting with contactless mobile payments for years, 2011 is expected to be the year the technology really takes off. That's because millions of phones capable of making contactless payments are expected to be shipped out in 2011.

As a result, this pay-by-phone market is forecast to make up $22 billion in transactions by 2015, up from "practically none" last year, according to research firm Aite Group.